This invention relates to an optical pickup and an optical drive used for the reproduce or record operation of an optical disc.
A conventional optical pickup carrying a two-wavelength multilaser is known in which a DPP (differential-push-pull) method is used for generating a tracking error signal and an astigmatic detection method for generating a focusing error signal. In such an optical pickup, the detection area pattern of the detector is formed of two columns each having three detection areas in a row (hereinafter referred to as the 3-by-2 detection area pattern), and the tracking error signal and the focusing error signal are generated by the signal of each detection area (see, for example, JP-A-2003-272218, or especially, Claim 13, FIGS. 5 and 6 thereof).
Also, a technique has been disclosed in which the 3-by-2 detection area pattern described in JP-A-2003-272218 is simplified to reduce the cost of the detector (see, for example, JP-A-2005-85369, or especially, Claim 9, FIG. 2 thereof).